<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
</html>
<script>
    //值传递  与 引用传递
    function  text1(num) {
        return num++
    }
    var abc = 123;
    text1(abc);
    console.log(abc)
</script>